1. Chapter 8 Class 10 Introduction to Trignometry
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Question 8 - NCERT Exemplar - MCQ - Chapter 8 Class 10 Introduction to Trignometry

Last updated at Dec. 16, 2024 by Teachoo

If cos (α + β) = 0, then sin (α – β) can be reduced to

(A) cos β   (B) cos 2β   (C) sin α   (D) sin 2α

Transcript

Question 8 If cos (α + β) = 0, then sin (α – β) can be reduced to (A) cos β (B) cos 2β (C) sin α (D) sin 2α Given that cos (α + β) = 0 cos (α + β) = cos 90° Comparing angles α + β = 90° α = 90° − β Now, sin (α – β) = sin (90° − β − β) = sin (90° − 2β) Using cos A = sin (90° − A) = cos 2β So, the correct answer is (B)
  1. Chapter 8 Class 10 Introduction to Trignometry
  2. Serial order wise

    3. NCERT Exemplar - MCQ

    sin 90 - θ, cos 90 - θ formula →
sin 90 - θ, cos 90 - θ formula →
Chapter 8 Class 10 Introduction to Trignometry
Serial order wise

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo